Magnetostrictive grinding machine



R. L. HAZELTON MAGNETOSTRICTIVE GRINDING MACHINE Jan. 17, 1961 2 Sheets-Sheet 1 Filed Sept. 18, 1956 N wE ON w INVENTOR. RICHARD L. HAZELTON ATTORNEYS Jan. 17, 1961 R. L. HAZELTON MAGNETOSTRICTIVE GRINDING MACHINE Filed Sept. 18, 1956 2 Sheets-Sheet 2 F|G.4 FIG. 5

FLYWHEEL WINDING WHEEL l OSCILLATOR INVENTOR.

PULLEY 58' IG- 7 RICHARD L. HAZELTON Jay' Jay ATTORNEYS United States Patent MAGNETOSTRICTIVE GRINDING MACHINE Richard L. I-Iazelton, Fairview- Park,- 0hio,;assignor to Omni American Engineering. Company, Cleveland;

Ohio, a partnership Filed Sept. 18,4956; Ser; No; '61( ,468

2 Claims. (Cl. 51- 34) This application, relating as indicated to a magneto-- strictive' grinding machine, isparticularly 'directed toa machine employing the use of a magnetostrictive device for grinding, lapping or abrading awork piece ortool.

In this invention an oscillatoryor'vibratory'motion by means of a magnetostrictor is given to a grinding wheel, and this is accompanied by a rotary motion perpendicular to said oscillatory or vibratory motion to provide an abrading action. These oscillatory motions, as for example, by means of a magnetostrictor are imparted to an abrasive, i.e., a grinding Wheel and the like while rotating, which in turn removes the material or particles from the surface that it contacts. It may be appreciated that the oscillatory motion may be imparted to the work piece a pattern set up by the combination of the oscillatory and rotary motions, which provides a changing face, smoother and more rapid abrading.

A further object of this invention is to develop a grinding, lapping or abrading employing a magnetostrictor and in doing so it is the intention to remove particles from a work piece more accurately and more efliciently by.

constantly renewing the abrading surface.

Another object of this invention is to combine in a single machine for performing such an abrading action at the same time the use of the magnetostrictive device to remove particles from a work piece at high frequencies in an oscillatory manner perpendicular to the rotary motion of the work piece and at the same time parallel to the surface being abraded.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the following description setting forth in detail one approved machine for carrying out the inventiomsuch disclosed machine, however, constituting but one ofthe various ways in which the principles of the invention may be used.

In the drawings:

Fig. 1 is an axial cross-sectional view through the magentostrictive grinding machine, showing the assembly components thereof;

Fig. 2 is an axial enlarged cross-sectional view of the oil and dust seal assembly for the grinding machine;

Fig. 3 is a cross-sectional view along the line 3-3 of Fig. 1;

Fig. 4 is a cross-sectional view along the line 44 of Fig. 1;

Fig. 5 is u a schematic view of""the magnetostrictive grindingflmachiney I v Fig. 6' is. a schematic view of'a modification ofithe invention;v

Fig. 7 'isa further modification of the magnetostrictive effort being applied directly to the tool or needle holder rather than to the rotating; shaft; and

Fig.7- 8"'is. a perspective view 'of a typical bearing lock rin retainer 'asi. shown in" Fig; 1.

In lthis invention? when I' refer to ma'gnetostrictiomi'v Irefer'to th'e changeindihiension of a ferromagnetic material when itis placediin a magnetic field. When I refer to. ferromagnetic materials; I' meaniron, nickel and cobalt and alloys of thesethree, as well 'asth'e' "lesser known ferromagnetic materials, i.e.", the Heusler7alloys:

In general it may be saidthat the phenomena of mag netostriction' is wellknown" and" very well und'eifstood', as are" the oscillators and" theinsources" of oscilla'ttiorr: This invention employs this principle and uses a 'shaft attached to a rotating means, said shaft being of a magnetostrictive material, as above disclosed; andwhen this is placed in a magnetic field, forces are produced" within the body-tendingto enlarge or contract it. In' this case it is a tube, rodor shaft and when this is placed within the windingcarrying alternating-current, the rod or barwill vibrate longitudinally at the usual rate of magnetostrictors.

In connection-with this device it'will be appreciated that in the preferred embodiment I am showing a'pull'ey; and ashaft, said rotating shaft having magnetostrictive material, such as a nickel rod or'tube, and a stationary winding surroundingsaid tube with enough space'to' allowfree rotation; wheel. It will'be understood that the'method of this invention can be applied to other machines and is not limited to this structure. In a number ofinstancesthe; work piece and the tool holder, as shown in Fig. 7, will be vibrated in a similar manneras by means of a'mag-u netostrictor, and this tool holder will be in contact with; a peripheral abrading surface.

In one embodiment of this invention shown in connection with Fig. 1, 10 shows a pulley having a groove'11: therein for a rubber belt or the like. 12 shows a pulley mandrel and 13 shows a plurality oflock nuts thereon retainingthe'pulley on the pulley mandrel. a key and keyway' to lock the pulley on the shaft. 15 shows an'oil and dust seal assembly, the components of: which are shown in greater detail inconnection. with Fig;-

2, having on-the exterior side thereof at16 an oil seal: retainer cup and adjacent thereto an annular dust seal:

felt washer 17 surrounding the shaft, and adjacent thereto towards the other components is the oil seal proper. 18- having a surface being held against the shaft by means of a tension spring 19,"said oilseal-gen'erallyybeing ;rein=- forced by means of a reinforcement member 20. The oil seal generally protects the magnetostrictive grinding as, for example, at 22 to the housing .rnember 23 which comprises an annular tubular element for the windings. Supporting the shaft and pulley mandrel 12 are a plurality of roller bearings shown generally at 24 and at one end thereof is a fly wheel 25 which is adapted to take the vibration of the magnetostrictive device on one side thereof. The fly wheel has welded to it as, for example, at 26 a nickel tube or rod acting as the shaft which lengthens or contracts by means of the magnetostrictive force. Within the housing is a locator sleeve 27 surrounding and substantially concentric with the winding, and this is secured to an insulated washer 28. A concentric core 29 is fastened to the washer 28. Within this At the end of theshaft is a grin'din'g 14 shows:

annular space are the windings to cause the magnetostrictive tube to vibrate or oscillate. When the tube vibrates, the fly wheel 25 is adapted to adsorb the vibrations from the magnetostrictor and dampen the shock before it reaches the roller thrust bearings 29, the inner ring of which is affixed to the shaft by means of adjustment and lock nuts, and the outer rings of which are affixed to the housing 23. These bearing elements secure the shaft so that it cannot move longitudinally with re spect to the hearings in either direction.

Details of the connection between the windings are shown particularly in connection with Fig. 3, which is a. cross-sectional view along the line 33 of Fig. 1. Here the housing is a tubular element 23. On the inside of this there is a locator sleeve 27 and an insulated core tube 29. The windings are between the locator sleeve and the core tube and are shown at 30. Within the insulated core tube there is an annular space 31, and the nickel shaft or tube 32. The connections to the windings are by means of a connector bolt 34 attached to one end of the winding through to a terminal nut 35 to the terminal connector 36, which in turn is connected to the lead wires 37.

The opposite end of the magnetostrictive grinding machine is shown in connection with Figs. 1 and 4 where 41 is the grinding wheel shaft or mandrel welded to the nickel tube as, for example, by a weld 42 having on the outside of the shaft a replaceable sleeve bearing 43 against which is a nylon bearing liner 44. The inner rings of the bearings are separated by a ring spacer 80. When the lock rings 52 are tightened, the inner rings and the spacer are held against the flange of the nylon bearing liner 44. The bearing is fastened to a keyway 47 shown in Fig. 4, and the balls for the roller hearing are shown at 48 with fibrous spacers 49 and the outer ring of the ball bearing 50. The inner race is held in position by means of a plurality of lock rings 52, as described above, and the outer race is secured to the housing 23 by means of a plurality of lock ring and seal retainers 53. An oil and dust seal assembly is shown generally at 54 and is similar to that disclosed in connection with 15. The grinding wheel is secured to the grinding wheel shaft by means of a lock ring nut 57, and a further front washer 56 held to the shaft by means of said nut. Between the grinding wheel 58 and the washer 55 is a centrifugal dirt repeller disc 59.

Fig. shows the entire assembly having the pulley secured as by means of some hold down device 60 attached to a fly wheel 25 surrounding the shaft, and then a winding 30 being connected to an oscillator shown at 62 to move the grinding wheel 58 perpendicular to its peripheral motion in order to provide a more even and regular grinding action.

Figs. 6 and 7 show alternate modifications in which a motor 82 in connection with Fig. 6 is directly coupled by means of a coupling 63 to the shaft of the magnetostrictive device. The oscillator is shown at 64 and a tool holder 65 holds a needle, for example, at 66 against the grinding wheel.

Fig. 7 shows a motor 67 attached to a shaft 68 which in turn is secured to a grinding wheel 69. A work holder generally shown at 70 has a magnetostrictive device 71 and an arm 72 having a tool holder 73 and securing a needle 74 so that it may be moved transversely of the peripheral motion of the grinding wheel.

In connection with this application, the method of abrading consists of moving an abrading surface with respect to a work piece at a very rapid rate in two directions by causing one of the members to move peripherally as, for example, a grinding wheel and by moving the wheel or the workpiece in an oscillatory manner perpendicularly thereto. This continually renews the work piece and provides for a fine finished abraded surface which is continually changed during the abrading action.

It is appreciated that this invention may be used in connection with needle sharpening where it is necessary to produce a very fine surface. This might well eliminate the need for a subsequent lapping of the needle to produce the fine surface.

Although the present invention has been described in connection with a few preferred embodiments thereof, variations and modifications may be resorted to by those skilled in the art without departing from the principles of the invention. All of these variations and modifications are considered to be within the true spirit and scope of the present invention as disclosed in the foregoing description and defined by the appended claims.

I claim:

1. A magnetostrictive grinding machine comprising a shaft member of a magnetostrictive material, a magnetic winding surrounding said shaft and spaced therefrom, and a high frequency electric current power source connected to said winding, a rotary driving means attached to said shaft, a housing for said winding, a hearing between said shaft and said housing, said bearing being capable of permitting the amount of longitudinal movement caused by the distortion of a magnetostrictive effect, a grinding wheel attached to the opposite end of said shaft.

2. A magnetostrictive grinding machine comprising a shaft member of a magnetostrictive material, a magnetic winding surrounding said shaft and spaced therefrom, and a high frequency electric current power source connected to said winding, a rotary driving means attached to said shaft, a housing surrounding said shaft and winding, a thrust bearing between said shaft and said housing, means for continually rotating the shaft, a fly wheel on said shaft to dampen the vibration of the magnetostrictive efiect, a further hearing at the opposite end of the magnetostrictive grinding machine between said shaft and said housing, said bearing adapted to permit a limited longitudinal movement caused by the magnetostrictive eifect, and a grinding wheel on the opposite end of said shaft.

References Cited in the file of this patent UNITED STATES PATENTS 295,900 Birkenhead Apr. 1, 1884 1,849,868 Einstein Mar. 15, 1932 2,070,944 Hillix Feb. 16, 1937 2,128,675 Indge Aug. 30, 1938 2,351,169 Weinland June 13, 1944 2,441,158 Krasnow May 11, 1948 2,736,144 Thatcher Feb. 28, 1956 2,818,686 Weiss Jan. 7, 1958 

